Calculator



May 5, 1925. 1,536,536

J. A. SMITH CALCULATOR Filed Deo. 3, 1923 3 Sheets-Sheet l INYFJITOR:

May 5, 1925.

J. A. SMITH CALCULATOR Filed Dec. 5, 1923 5 Sheets-Sheet 2 May 5, 1925.1,536,536 fJ. A. SMITH CALCULATOR Filed Dec. 3, 1925 3 Sheets-Sheet I5cuH- Shri/b.

u? will', atto: e111 Patented May 5, 1925.

UNITED STATES `JOHN ANTHONY SMITH, 0T sPoxANE, WASHINGTON.

CALCULATOR.

Application led December 3, 1923. Serial N'o. 678,297.

-To all whom t may Be it known that I.' JOHN A. SMITH, a citizen of theUnited States, residing at Spokane', in the county of Spokane and Stateof Washington, have invented certain new and4 -'sides of the slot beingdefined by ribs 160 struck up from the face plate, as best shown in Fig.4. Above the said central longitudinal slot 2, the face plate isprovided with a transverse series of longitudinal slots 3 usefulImprovements in Calculators, of \t\hrough which a pencil or pointedinstruwhich the following is a speoilicatiomv This invention relates tocalculators of the type disclosed in Letters Patent, No. 1,422,944,granted to I-I. S. Edmondson, July 18, 1922. One object of the presentinven'v tion is to provide a cover which may be manipulated to serve asa stand or support for the calculator when it is in use, and anotherobject of the invention is to provide a construction whereby the severalparts of the calculator may be stamped from sheet metal so that hecompleted device will be light, compact and durable. A still furtherobject of the invention is to provide a construction whereby, theseveralv parts of the calculator may be rapidly assembled and, whenassembled, held in compact operative relation without employing anypermanent securing means, and yet another object of the invention is toprovide means whereby the number strips may be all returned to zeroposition after use by a single movement of a setting element. OtherObjects of the invention will appear incidentally in the course of theJfollowing description.-

In the accompanying drawings:

Figure 1 is a front elevation of the improved calculator arranged foruse;

Fig. 2 is a side elevation of -the same;

Fig. 8 is a longitudinal section on the line 3-3 of' Fig. 1, the devicebeing arranged to be carried in a pocket;

Fig. 4 is a transverse section on the line 4-4 of Fig. 1;

Fig. 5 is a detail section with parts in plan taken upon the line 5-5 ofFig. 4;

Fig. 6 is adetail section on the line6-6 of Fig. 5;

Fig. 7 is an edge view showing the device arranged for use in the hand;

Fig. 8 is a plan view of the guide plate;

Fig. 9 is an edge view of one of the nurnber strips, and

Fig. 1() is a detail view of the clearin bar.

In carrying out my present invention, I employ a face plate 1 which isprovided in its lower portion with a central longitudinal slot 2enlarged at itslower end for a `purpose which will presently appear,.the

nient is to be inserted to manipulate the proper strips in the mannerset forth in deta1l 1n the patent to Edmondson hereinbefore mentioned,while above the said transverse .series of longitudinal slots the faceplate. 1s provided with a transverse row of openings 4 through which thedigits upon the number strips may be read to note the result of anaddition or subtraction. The face plate is provided at all its edgeswith the rearwardly extending walls 5 whereby a housing is provided forthe number strips and the parts supporting the same. The

edge portions of the side and bottom walls 5 are turned laterallyoutward to form flanges 6. The top wall 5- is merged into a dependinglip or flange 7 which constitutes a partial back wall, as shown clearlyin Fig. 3. A guide plate 8 is employed, and this guide plate is ofproper dimensions to lit closely but easily within the side and endwalls of the face plate and 'between the main body of the face plate andthe lip or flange 7, as shown clearly in Fig. 3. The side edges of thisguide plate are struck up, as indicated at 9, toV form flanges which, bybearing against the inner surface of the face plate 1, will serve toproperly space the two plates and provide a chamber in which the numberstrips 10 mayveasily-slide. The guide plate 8 is also provided on itsupper face with beads or ribs 11 forming between them `channels orgrooves in which the number strips' may slide and by which they will beguided, as will be readily understood upon reference to Figs. 5 and 6.These guiding ribs may be conveniently formed by striking up a portionof the guide plate, as clearly shown in Fig, 6. The guiding ribs willextend to points adjacent the ends of the slots 3 in the face plate andwill also extend from points above the upper ends of said slots topoints near the upper-end of the face plate so that they will oil'er noobstruction to the lateral movement of the manipulating tool in theoperations of addition and subtraction but at the same time will besuiliciently extensive to provide complete operative guides for thenumber strips. The said number strips are provided with notches 12 intheir side edges to be engaged by a manipulating tool as set forth fullyin the above mentioned patent and the upper portions of the strlps arefinished in a color contrasting wlth the color of their lower portionsfor the purpose particularly set forth in said patent. To ald in readingthe results attained by the use of the calculator, the surface of theface plate adjacent the several slots 3 is given different colors sothat the tens and units may be readily distinguished from the hundreds,and the hundreds readily distinguished from the thousands. Reverselyarranged series of tigures, indicated at 13, are also displayed upon theface plate adjacent each slot 3 to be referred to when any particularoperation of addition or subtraction vis to be performed, it beingunderstood that my present calculator is operated in exactly the samemanner as the calculator disclosed in the aforesaid patent. The numberstrips are `bowed longitudinally, as shown in Fig. 9, whereby they willfrictionally engage the opposed surfaces of the face plate and the guideplate with sullicient-tension to remain in any position in which theymay be set. A small teat 11 is struck up from each strip adjacent itslower end, and these several teats are adapted to bear against the innersurface of the face plate between the several slots 3 therein so thatthe area of contact with the face plate will be reduced and liability ofthe strips to defacement overcome. 'A setting or clearing bar or strip15 isv provided, and this setting bar or strip is placed upon the guideplate 8 between the same and the face plate and is guided at one end bythe adjacent flange 9 and at its opposite end by a rib 90 struck up fromthe guide plate and alined with the corresponding rib 11, as shown inFigs. 5' and 8. This clearing bar is provided between its ends with anupstanding knob or handle element 16. This knob or handle member ispreferably struck up from the bar and may be of any approved form,although in the present drawings I have shown it as substantiallyT-shaped,

having a head which is adapted to be passedA upwardly through thewidened lower end 17 of the guide slot 2, and a shank which is adaptedto enter and play in the slot 2 upon upward movement of the evener orsetting bar with the head projecting over the sides of the said slot andresting upon the ribs 160, as clearly shown in Fig. 4. The head isprovided with a notch 161 in that edge of its shank which is presentedto the number strips so as to accommodate the web 162 in the face platebetween the slot 2 and the alined slot 3, thereby permitting the edge ofthe bar to project under said web and push the number strips fully hometo the zero position. In assembling the parts, the number strips aresimply placed upon the upper surface of the guide and supporting theguide plate with its knob disposed 'substantially on the centrallongitudinal line of the plate, after which operation the upper vend ofthe guide plate is engaged between the lip or flange 7 and the body ofthe face plate, and then pressed toward the face plate so that the knob16 will pass through the widened lower end 17 of the guide slot 2. Theevener bar is then pushed upwardly along the slot 2 and will thus bebrought into contact with the lower ends of all the number strips andwill push the same upwardly until their movement is arrested by thecontact of their upper ends with .the top wall of the face plate. Whenthe strips have been thus positioned, the nought or zero digit upon thestrips will appear at the respective openings 4 in the face plate. Toretain the guiding and supporting plate 8 within the chamber provided bythe face plate and its walls, I provide a back plate 18 which is formedat Aone end and both side edges with reentrant flanges 19 adapted toengage around the flanges 6 of the face plate and slide upon the same sothat the back plate will be readily and efectually assembled with theface plate and will serve 'as an eiiicient means for retaining theguiding and supporting plate 8 in place. rllhe back plate is of lesslength than the face plate and the guiding and supporting plate so thatthe upper end of the back plate will, when the parts are assembled, bespaced from the back lip 7, while the lower end of the back plate willhave its flange 19 engaged with tle bottom flange 6 of the face plate,the extent to which the back plate may be pushed toward the top of theface plate being thus limited. l',

The parts so far described constitute a complete operative calculator,the number strips of which may be manipulated by the insertion of apencil point through the proper slots 3 to engage notches 12 in therespective number'strips. I provide, however, a stylus 20N which may beengaged through an eye or sleeve 21 formed upon one edge of the backplate so that a suitable manipulating tool will be at hand whenever theuse of the device is desired.

To further protect the parts from: injury when the device is not in use,I provide a cover consisting of front and back plates 22 and 23lpreferably covered with leather which is extended between the adj aoentedges of said plates, as indicated at 24, to constitute a hinge. Theback plate is preferably divided transversely near one end so 'that theleather covering will form a hinge or fold, as shown at 25', and to theend section of the back plate, I secure a retaining plate 26 which isadapted to engage between the backing plate 18 and the guiding andsupporting plate 8 and fits snugly therebetween So that it will serve tohold the guiding plate and the number strips resting thereon firmlyagainst the face plate whereby the parts will be maintained in properoperative relation at all times. The end of the retaining plate 26 isadapted to abut the edge of the back lip 7 so that, when the cover hasonce been assembled with the other parts, it cannot be accidentallyremoved, although it may be easily withdrawn when necessary by merelyspringing the free end of the back 23 slightly away from the said backlip 7. The free ends of the front and back leaves or members of thecover are provided with stud and socket fastening members 27 whereby thecover may be held in closed position, as shown in Fig. 8, when thedevice is to be carried in a 4garment pocket. Then the device is to beused, the front leaf of the cover may be swung into a horizontalposition, as shown in Fig. 2, with the lower end of the back plate 18resting against the fastening member 27, whereupon the said leaf 22 willconstitute a base and support for the device, while the leaf 23 willconstitute a brace and the fastening member 27 will serve as a stop toprevent collapse of the device as thus set up. This arrangement isclearly shown in Fig. 2 of the drawings and brings the calculator into aposition where it may be very easily and conveniently manipulated by theuser. The front leaf 22 may, however, be merely folded over the backleaf, as shown in Fig. 7, so that the device may be held in the hand inthe same manner as a writing tablet.

From the foregoing description, taken in connection with theaccompanying drawings,

it will be seen that I have provided a construction whereby the severalparts may be ver easily assembled and, when assembled, will be broughtinto such compact and close relation that no extraneous fasteningdevices are needed and the parts will be effectually held againstaccidental separation. The construction, however, is such that, if,through some accident or other cause, an element should be broken or sobadl bent or otherwise damaged as to render tlie use of the deviceuncertain or impractical, the parts maybe easily disassembled to permitsuch vrepalrs as may be necessary or the substitution of a new part forthe damaged part. The construction devised by me facilitates the shapingof the several elements in stamping presses so that the device may beproduced very economically and placed upon the market in a very durableform.

Having thus described the invention, I claim:

l. In a calculator, the combination of a face plate, a guide platesupported below the face plate, and a plurality of bowed number stripsslidably mounted upon the guide plate between the same and the faceplate and provided at their lower ends with projections btlearingagainst the under surface of the face p ate.

2. In a calculator, the combination of a face plate having marginal top,bottom and side walls projecting rearwardly therefrom and a back lipdepending from its top wall parallel with the face plate, a guide platehaving one end engaged between the said back lip and the face plate andabutting the top wall of the face plate, the said guide plate fittingclosely within the walls of the face plate and provided along its sideedges with fianges bearing at their outer sides against said walls andat their edges against the under surface of the face plate, a back platecarried by the bottom and side walls of the face plate, means abuttingthe back lip and resting on the back plate for holding the said guideplate to the face plate, and a plurality of number strips slidablymounted upon the said guide plate between the same and the face plate.

3. In a calculator, the combination of a face plate having openingstherethrough, a guide plate disposed below the face plate and havinglongitudinal guide ribs struck up therefrom, said ribs bearing againstthe. under surface of the face plate, number strips slidabl supported onthe guide plate. between saidy ribs, a back plate engaged marginallywith the face plate, and a cover having a member engaged between theback plate and the guide plate and holding the guide plate to the faceplate.

In testimony whereof I afiix my signature.

JoHN ANTHONY SMITH. [1.. a]

